2. Water
Water is an inorganic, transparent,
tasteless, odorless, and nearly colorless
chemical substance, which is the main
constituent of earth's hydrosphere and the
fluids of all known living organisms.
3. Uses of Water
Water can be used for direct and indirect purposes. Direct purposes include bathing, drinking,
and cooking, while examples of indirect purposes are the use of water in processing wood to
make paper and in producing steel for automobiles. The bulk of the world’s water use is for
agriculture, industry, and electricity. The most common water uses include:
Drinking and household needs
Recreation
Industry and commerce
Agriculture
Thermoelectricity/energy
4. Sources of Water Supply
Rain
Surface Water
1. Impounding Reservoir
2. River And Streams
3. Lakes And Ponds
Ground Water
1. Sallow Well
2. Deep Well
3. Spring
6. Histopathology
The inflammatory infiltrate of early yaws lesions is composed mainly of plasma
cells and lymphocytes and less commonly neutrophils and eosinophils. In
contrast with venereal syphilis, the blood vessels show limited or no endothelial
proliferation. With the aid of silver staining, Treponemes can be visualized in
the intercellular spaces of the epidermis, among inflammatory cells, and within
the dermis. The histopathology of late yaws lesions resembles that of tertiary
syphilis, with the presence of granulomas associated with necrotic areas.
7. Pathogenesis
Aside from establishing phylogenetic relationships among Treponemal species and
subspecies, the aid of comparative genomics was also sought to explain the lower
degree of virulence associated with T. Pallidum subsp. Per tenue than with T.
Pallidum subsp. Pallidum. Unlike syphilis, yaws is said not to be vertically
transmitted or to affect the central nervous system, rather being limited to skin, joints,
soft tissues, and bones. The very limited genetic diversity between these pathogens
was already established in the 1980s, when hybridization experiments were performed
using DNA from yaws and syphilis strains . The results of these experiments
suggested that the degree of genomic diversity between these pathogens was lower
than the limit of resolution of the technique
9. Treponemal Infections and HIV
The interaction of t. Pallidum and human immunodeficiency virus (hiv) in coinfected
individuals is poorly understood and has been examined only in the setting of syphilis.
Rompalo et al. Reported that hiv coinfection may have a limited effect on the clinical
manifestations of primary and secondary syphilis: patients with primary syphilis and
hiv tended to exhibit multiple ulcers at the site of inoculation more frequently than
hiv-negative patients, and hiv-infected individuals presented more often with unhealed
primary ulcers along with secondary manifestations (67). The cutaneous rash that is
commonly associated with secondary syphilis has occasionally been reported to be
atypical in hiv-infected patients
10. DIAGNOSTIC TOOLS FOR ENDEMIC
TREPONEMATOSES
In the absence of laboratory confirmation, the diagnosis of syphilis, yaws, bejel, or pinta
has traditionally been based upon the careful analysis of the patient's symptoms and
signs, in combination with knowledge of the epidemiological context of human
treponematoses. In the laboratory, the available diagnostic tools for endemic
treponematoses and venereal syphilis are limited to two generic categories: direct
detection of treponemes in biological specimens (including molecular assays) and
serological tests. Although serology remains the most common diagnostic method for
treponemal infection, none of the available serological tests is able to differentiate
among the agents of these diseases. This ability is currently limited to molecular
methods that target genetic signatures thought to be specific to each subspecies in
resource-limited settings.
